A large area of Lake Ontario was searched, but neither the pilot nor the aircraft was found. The last known position of aircraft C-GXGB is 14 miles northeast of Hamilton Airport over Lake Ontario. The weather conditions where the pilot was holding were visual meteorological conditions (VMC). The loud background noise in the pilot's radio transmissions, evident at the time the pilot announced his predicament and afterwards, was not evident on his initial communications with the tower controller. This audible change, accompanied by an erratic flight path, indicates that the aircraft's windshield was broken and that the pilot was incapacitated as a result. Because the aircraft and pilot are still missing, the nature of the object that broke the aircraft's windshield was not determined.2.0 Analysis A large area of Lake Ontario was searched, but neither the pilot nor the aircraft was found. The last known position of aircraft C-GXGB is 14 miles northeast of Hamilton Airport over Lake Ontario. The weather conditions where the pilot was holding were visual meteorological conditions (VMC). The loud background noise in the pilot's radio transmissions, evident at the time the pilot announced his predicament and afterwards, was not evident on his initial communications with the tower controller. This audible change, accompanied by an erratic flight path, indicates that the aircraft's windshield was broken and that the pilot was incapacitated as a result. Because the aircraft and pilot are still missing, the nature of the object that broke the aircraft's windshield was not determined. 3.0 Conclusions 3.1 Findings The pilot was qualified and competent. The aircraft was being operated in visual meteorological conditions when the windshield was struck by an unknown object. The object penetrated the windshield and caused the pilot to become incapacitated. The aircraft was last observed on radar 14 miles northeast of Hamilton Airport over Lake Ontario. An extensive search was conducted but neither the aircraft nor the pilot was found. 3.2 Causes An unknown object penetrated the aircraft windshield and incapacitated the pilot. The Board has no aviation safety recommendations to issue at this time.4.0 Safety Action The Board has no aviation safety recommendations to issue at this time.